by reeds (vibrating tongues) fitted to organ-pipes of particular construction. The manner of formation of vowels by the voice is shortly this. There are situated in the larynx a pair of vibrating membranes called the vocal chords, which may be rudely imitated by stretching a piece of sheet india-rubber over the open end of a tube, so as to form two half-covers to it, 'like the parchment of a drum split across the middle;' when the tube is blown through, the india-rubber flaps will vibrate as the vocal chords do in the larynx, and give out a sound. In the human voice, the musical effect of the vibrating chords is increased by the cavity of the mouth, which acts as a resonator or sounding-box, and which also, by its shape at any moment, modifies the musical 'quality' or 'timbre' of the sound produced. This, not the less felt because its effects are not registered in musical notation, depends on the harmonic overtones accompanying the fundamental tone which alone musical notation takes account of. It makes the difference between the same note on two instruments, flute and piano for instance, while some instruments, as the violin, can give to one note a wide variation of quality. To such quality the formation of vowels is due. This is perfectly shown by the common Jew's harp, which when struck can be made to utter the vowels a, e, i, o, u, &c., by simply putting the mouth in the proper position for speaking these vowels. In this experiment the player's voice emits no sound, but the vibrating tongue of the Jew's harp placed in front of the mouth acts as a substitute for the vocal chords, and the vowel-sounds are produced by the various positions of the cavity of the mouth, modifying the quality of the note, by bringing out with different degrees of strength the series of harmonic tones of which it is composed. As to musical theory, emotional tone and vowel-tone are connected. In fact, an emotional tone may be defined as a vowel, whose particular musical quality is that produced by the human vocal organs, when adjusted to a particular state of feeling.
Europeans, while using modulation of musical pitch as